Current articulated couplings on a common bogie comprise a sole plate connected to one of the vehicles, supported on the common bogie by springs, and carrying a ball on elastomer members with the top surface of the ball bearing against a spherical bearing surface connected to the other vehicle. Such articulated couplings including spherical surfaces require a great deal of machining. They are expensive and relatively heavy.
Canadian Pat. No. CA-1 218 900 describes an articulated coupling for rail cars making use of a common bogie, in which the ends of the bodies of the two vehicles are pivotally mounted on the axis of a cylindro-conical connection part which is connected by means of an annular part made of elastomer to a bowl on the bogie. This articulated coupling does not allow one of its parts to be at an angle relative to the vertical axis so as to enable one vehicle to tilt relative to the other when entering or leaving lengths of track which are banked, and when passing over humps and dips.
The object of the present invention is to provide an articulated coupling which is cheap, relatively lightweight, and which also provides the necessary functions, even when applied to high-speed trains. It should enable parts to rotate relative to each other so that the train can negotiate curved track, and it should also allow one of its parts to take up an angle relative to the vertical axis in order to enable one vehicle to tilt relative to the other. In addition to responding to traction and braking forces in normal operation, it must also respond to forces due to exceptional shocks, within predetermined limits. It must be possible to raise the common bogie by applying hoisting forces to the vehicles during re-railing operations. Coupling and decoupling must be capable of being performed quickly.